Edward ii



(No Model.)

B. H. JOHNSON. AUTOMATIC GUT-OUT FOR INGANDESGENT LAMPS.

No. 515,960. Patented Mar. 6, 1894.

UrrrrEn STATES PATENT FFIQEQ EDlVARD ll. JOHNSON, OF NElV YORK,ASSIGNOR TO THE GENERAL ELECTRIC COMPANY, OF NEYV YORK, N. Y.

AUTOMATIC CUT-OUT FOR INCANDESCENT LAMPS SPECIFICATION forming part of Letters Patent No. 515,960, dated March 6, 189%,

Application filed May 17,1886. Serial No. 202,379. tile modelil To a whom it may concern.-

Be it known that 1, EDWARD H. JoHNsoN, of New York city, in the county and State of New York, have invented a certain new and 5 useful Improvement in Systems of Electric Lighting, of which the following is a specifi cation.

My invention is designed to simplify and cheapen the construction of electric light plants wherein incandescent electric lamps arranged in series are employed.

The principal feature of my invention is the production of a device whereby when a lamp is broken, the same will be cut out of r circuit and if desired another lamp or an equivalent resistance will be thrown into circuit in place of the broken lamp by the soldering action of an electric arcinduced between wires located in soldering proximity.

A further feature of my invention is the production of a soldering cut-out or switch separate from the lamp, for accomplishing the throwing into circuit of a lamp or equivalent resistance as stated.

The invention of this separate switch or cut-out is one generally applicable for purposes of closing circuit around an electric lamp or other electrical instrument whether the shunt closed by it is one of low or prac' o tically no resistance or includes a lamp or other resistance.

In the accompanying drawings, forming a part hereof Figure l, is an elevation and partial section of an incandescent electric lamp 5 and socket embodying the first feature of invention. Figs. 2, 3 and 4, are diagramsillustrating arrangements of the lamp shown in Fig. 1 in connection with other lamps and resistances; Fig. 5, a vertical section illustrato ing a construction for the separate cut-out or switch; Fig. 6, a detail section of the parts at the soldering point of this device; and Fig. 7, a diagram illustrating the separate cut out or switch in circuit.

5 The incandescent electric lamp A has introduced into its neck a in addition to the ordinary leading in wires Z) c, a third or bridge wire d, which terminates in such neck and is brought into soldering proximity with one of the leading in wires, in this case with wire I). This may be done by a double-barrel glass tube a through one barrel of which the wire 1) passes, the wire d beiugintroduced into the other barrel of the tube. Above the doublebarrel glass tube, the end of bridge wire d projects and at this point the wires and d are in soldering proximity. Bridging the wires b d at this point is a materialf which normally is of such high resistance that when the carbon of the lamp is entire, little or no current will flow across this bridge, but when the carbon breaks the bridge f will induce an arc to spring across wires 1) (Z which will be connected with the circuit on opposite sides of the broken carbon, and the wires Z) (Z will be fused and soldered together by the arc. The materialf may be peroxide of lead with a suitable binding substance such as mucilage as described in my application, Serial No. 197,626, filed April 3, 1886.

The base B of lamp A has two metal terminals g and h for the leading in wires 1) c and a third metal terminal t for the bridge wire d. It screws into a socket or holder O having corresponding terminals from which run the circuit wires 1, 2 and the bridge wire The lamp A is introduced by wires 1, 2, into a circuitd, 5 in which other similar lamps are located in series therewith. lVire 3 forms part of a bridge circuit 8, 6, bridging through So are inducing material f the carbon of the lamp. This bridge circuit when closed by the soldering of wires 7) (Z may have practically no resistance as shown in full lines in Fig. 3, or it may be provided with a wire resistance R equal to the resistance of a lamp as shown in dotted lines in Fig. 3. Or the bridge circuit 3, 6, may include another lamp which will be thrown into circuit when the first lamp is broken. As indicated by diagram in Fig. 4: this second lamp may be one, 0, like the lamp described in my applica tion Serial No.197,626, having its leadingin wires located in soldering proximity and bridged by are inducing material fso that 5 when the carbon of lamp 0 breaks the circuit will be closed by the soldering together of its leading in wires. Or the second lamp may be one, A, similar to lamp A, and itself closing, when its carbon breaks, a bridge cir- IOO cuit of no resistance or including a lamp o equivalent resistance.

Another feature of the invention is the construction of the soldering switch or cut-out as a device separate from the lamp. This separate switch or cut-out is composed of two wires lo Z brought into soldering proximity at their free ends where they are bridged by a body m of the arc inducing material. The wires Z may be held by a double-barrel glass tube n. This separate soldering cut-out or switch is located in a shunt 7, 8, around a lamp D, said shunt including a lamp or equivalent resistance or being when closed a shortcircuit. The separate cut-out or switch is constructed for introduction into this shunt in any suitable way. A convenient form is to introduce the parts into a plug E, provided with a screw terminal 0 and a tip terminal 19, to which the wires k 1 run. This plug screws into a socket F having corresponding terminals connected with the wires of shunt 7, 8.

When the carbon of lamp D breaks, an arc will spring in the separate cut-out or switch between wires 10 l, and these wires will be soldered together, closing the line around the broken lamp, and, if desired, completing circuit through a lamp or equivalent resistance normally out of circuit.

What I claim is 1. The combination with an electric circuit and an incandescent electric lamp located therein, of a normally open bridge circuit through the conductors of which no current passes normally, and wires in such bridge circuit located in soldering proximity, so as to fuse and solder together by the springing of an arc across them, said wires being bridged by an arc inducing material which is normally an insulator but which by heat is reduced to a conducting state, substantially as set forth.

2. The combination with an electric circuit and an incandescent electric lamp located therein, of an auxiliary lamp or equivalent resistance located in a bridge circuit through which no current passes normally, and wires in such bridge circuit located in soldering proximity so as to fuse and solder together by the springing of an arc across them, said wires being bridged by an arc inducing material, substantially as set forth.

3. A separate cut-out or switch, composed of two wires located in soldering proximity and bridged by an arc inducing material which is normally an insulator but which by heat is reduced to a conducting state, substantially as set forth.

4. A separate cut-out or switch, composed of two wires located in soldering proximity and bridged by an arc inducing material, which is normally an insulator but which by heat is reduced to a conducting state, in combination with separable circuit connections, substantially as set forth.

5. The combination with a holder or socket having circuit terminals, of a plug having corresponding terminals entering such socket, wires connected with the terminals of said plug and located in soldering proximity, and an arc inducing material bridging such wires, substantially as set forth.

6. An incandescent electric lamp having three contact terminals two of which are connected respectively to the terminals of the filament while the other forms with one of the terminals of the filament an automatic cut-out adapted to complete the connection to said contact upon the rupture of the incandescent conductor.

7. The combination with. an incandescent electric lamp, of an auxiliary lamp wire connected to a cut-out device within the lamp itself and adapted to be operated by the are forming on rupture of the incandescing conductor, and a reserve lamp in uninterrupted connection with said auxiliary wire, as and for the purpose described. 7

8. An incandescent electric lamp having a base provided with three connecting electrodes or contacts, in combination with a lamp support having three corresponding c0nnecting electrodes, two of said electrodes in the lamp being connected with the terminals of the filament while the third connects with a third terminal which with one of the filament terminals forms a cut-out device within the field of the are forming on rupture of the filament.

This specification signed and witnessed this 12th day of May, 1886.

EDWARD H. JOHNSON. Witnesses:

WM. PELZER, E. O. ROWLAND. 

